Alarm systems are often used to warn users of potentially dangerous conditions. For example, an alarm system for a residential structure (e.g., a house, apartment, or condominium) can include an alarm system that warns the structure's occupants of hazards such as smoke, fire, and security breaches (e.g., intrusions or burglaries). An alarm system can provide auditory and/or visual warnings, for instance by emitting a warning sound (e.g., using a siren, horn, bell, or speaker), and/or displaying a visual warning (e.g., using a flashing strobe light). To increase the likelihood that a user will be adequately warned in the event of a hazardous situation, alarm systems can be tested periodically to verify that they are functioning as intended.